The latest articles on DEV Community by liranye (@liranye). https://dev.to/liranye https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F506796%2F88b6c7e9-bfb9-4448-bc62-c90580ccbd72.png https://dev.to/liranye en liranye Sun, 13 Jun 2021 18:54:52 +0000 https://dev.to/liranye/when-your-first-docker-compose-fails-and-you-don-t-know-why-3oj2 https://dev.to/liranye/when-your-first-docker-compose-fails-and-you-don-t-know-why-3oj2 <p>check these solutions </p> <div class="ltag__stackexchange--container"> <div class="ltag__stackexchange--title-container"> <div class="ltag__stackexchange--title"> <h1> <img src="https://res.cloudinary.com/practicaldev/image/fetch/s--7Gn-iPj_--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev.to/assets/stackoverflow-logo-b42691ae545e4810b105ee957979a853a696085e67e43ee14c5699cf3e890fb4.svg" alt=""> <a href="https://stackoverflow.com/questions/67794230/unreachable-db-container-in-a-multi-container-application-django-db-utils-oper/67878280#67878280" rel="noopener noreferrer"> <span class="title-flare">answer</span> re: unreachable db container in a multi-container application - django.db.utils.OperationalError: (2002, "Can't connect to MySQL server on 'db' (115)") </a> </h1> <div class="ltag__stackexchange--post-metadata"> <span>Jun 7 '21</span> </div> </div> <a class="ltag__stackexchange--score-container" href="https://stackoverflow.com/questions/67794230/unreachable-db-container-in-a-multi-container-application-django-db-utils-oper/67878280#67878280" rel="noopener noreferrer"> <img src="https://res.cloudinary.com/practicaldev/image/fetch/s--Y9mJpuJP--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev.to/assets/stackexchange-arrow-up-eff2e2849e67d156181d258e38802c0b57fa011f74164a7f97675ca3b6ab756b.svg" alt=""> <div class="ltag__stackexchange--score-number"> 0 </div> <img src="https://res.cloudinary.com/practicaldev/image/fetch/s--wif5Zq3z--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev.to/assets/stackexchange-arrow-down-4349fac0dd932d284fab7e4dd9846f19a3710558efde0d2dfd05897f3eeb9aba.svg" alt=""> </a> </div> <div class="ltag__stackexchange--body"> <p>On Centos8, The firewall is configured with nftables, which doesn't work well with docker. To fix this problem, open fw configuration file:</p> <pre><code>sudo vim /etc/firewalld/firewalld.conf </code></pre> <p>Update FirewallBackend=nftables to <strong>FirewallBackend=iptables</strong></p> <p>save this change and reload firewalld:</p> <pre><code>sudo systemctl restart firewalld.service </code></pre> </div> <div class="ltag__stackexchange--btn--container"> <a href="https://stackoverflow.com/questions/67794230/unreachable-db-container-in-a-multi-container-application-django-db-utils-oper/67878280#67878280" rel="noopener noreferrer">Open Full Answer</a> </div> </div> containers communication centos8